Plaster frame for luminaires

ABSTRACT

A plaster frame for a luminaire includes a first attachment tab on a side of the plaster frame and a second attachment tab on the side of the plaster frame. The plaster frame further includes a back wall. The first attachment tab and the second attachment tab each include a rib protruding toward the back wall. The back wall and the first attachment tab define a first space for a hanger bar assembly to extend therethrough, and the back wall and the second attachment tab define a second space for the hanger bar assembly to extend therethrough.

PRIORITY CLAIM AND RELATED APPLICATIONS

The present application is a continuation of and claims priority to U.S.patent application Ser. No. 14/579,997, filed Dec. 22, 2014, and titled“Adjustable Hanger Bar For Luminaires,” which is a continuation of andclaims priority to U.S. patent application Ser. No. 14/242,540, filedApr. 1, 2014, and titled “ADJUSTABLE HANGER BAR FOR LUMINAIRES,” whichclaims priority under 35 U.S.C. Section 119(e) to U.S. ProvisionalPatent Application No. 61/809,171, filed Apr. 5, 2013, and titled“Adjustable Hanger Bar For Luminaires,” the entire contents of which areincorporated herein by reference.

The present application is also related to U.S. Pat. No. 7,673,841,titled “HANGAR BAR FOR RECESSED LUMINAIRES WITH INTEGRAL NAIL” and filedon Mar. 25, 2005, the entire content of which is incorporated herein byreference.

TECHNICAL FIELD

The present disclosure relates generally to lighting solutions, and moreparticularly to an adjustable hanger bar for mounting a luminaire on asupport structure.

BACKGROUND

A luminaire (i.e., a light fixture) is typically a complete lightingunit consisting of one or more lamps, socket, and optical devices fordistributing light. A recessed luminaire is an example of a luminairethat is installed behind a structure such as a ceiling. Recessedluminaires are used in both commercial and residential applications. Forexample, a recessed luminaire is typically mounted on support structuresbehind a ceiling wall that has an opening to allow light from therecessed luminaire to illuminate an area below the ceiling wall.

Various support systems have been employed to support recessedluminaires. For example, recessed luminaires are often suspended betweensupport structures such as joists and T-bar structures. To illustrate, arecessed luminaire may be supported by hanger bars that extend betweenparallel support structures. Generally, hanger bars need to haveadequate strength and rigidity to reliably support a recessed luminaire.Further, because the spacing between the support structures such as thejoists of a ceiling structure may vary, adjustability of the lengths ofhanger bars is desirable for easy installation as well as forcompatibility with different support structures.

Improperly installed hanger bars can cause a recessed luminaire as wellas the hanger bars supporting the recessed luminaire to detach and fallfrom support structures (e.g., parallel joists). Further, unintentionaldetachment of hanger bar members from each other can make installationof hanger bars difficult. Hanger bars that are easy to install save timeand expense. Thus, adjustable hanger bars that simplify installation andreduce risk of improper installation are desirable.

SUMMARY

In general, the present disclosure relates to an adjustable hanger barfor mounting a luminaire on a support structure. In an exampleembodiment, a hanger bar assembly includes a first hanger bar memberthat includes a first rail segment. The first hanger bar member alsoincludes a first channel segment that includes a first channel. Thefirst hanger bar member also includes a first transitional middlesegment extending between the first rail segment and the first channelsegment. The first rail segment and the first channel segment are offsetfrom each other with respect to a horizontal axis. The hanger barassembly further includes a second hanger bar member that includes asecond rail segment. The second rail segment is positioned in the firstchannel of the first channel segment. The second hanger bar memberfurther includes a second channel segment that includes a secondchannel. The first rail segment is positioned in the second channel. Thesecond hanger bar member also includes a second transitional middlesegment extending between the second rail segment and the second channelsegment. The second rail segment and the second channel segment areoffset from each other with respect to the horizontal axis.

In another example embodiment, a hanger bar assembly includes a firsthanger bar member that includes a first rail segment. The first hangerbar member further includes a first channel segment that includes afirst channel. The first hanger bar member also includes a firsttransitional middle segment extending between the first rail segment andthe first channel segment. The first rail segment and the first channelsegment are offset from each other with respect to a horizontal axis.The hanger bar assembly further includes a second hanger bar member thatincludes a second rail segment. The second rail segment is designed tobe positioned in the first channel of the first channel segment. Thesecond hanger bar member further includes a second channel segment thatincludes a second channel. The first rail segment is designed to bepositioned in the second channel. The second hanger bar member alsoincludes a second transitional middle segment extending between thesecond rail segment and the second channel segment. The second railsegment and the second channel segment are offset from each other withrespect to a horizontal axis.

In another example embodiment, a luminaire mounting structure formounting a recessed luminaire that includes a first hanger bar assembly,a second hanger bar assembly, and a plaster frame. The first hanger barassembly is attached to the plaster frame on a first side of the plasterframe. The second hanger bar assembly is attached to the plaster frameon a second side of the plaster frame opposite the first side. Each ofthe first hanger bar assembly and the second hanger bar assemblyincludes a first hanger bar member and a second hanger bar member. Thefirst hanger bar member includes a first rail segment and a firstchannel segment that includes a first channel. The first hanger barmember further includes a first transitional middle segment extendingbetween the first rail segment and the first channel segment. The firstrail segment and the first channel segment are offset from each otherwith respect to a horizontal axis. The second hanger bar member includesa second rail segment, where the second rail segment is positioned inthe first channel of the first channel segment. The second hanger barmember further includes a second channel segment that includes a secondchannel, where the first rail segment is positioned in the secondchannel. The second hanger bar member also includes a secondtransitional middle segment extending between the second rail segmentand the second channel segment. The second rail segment and the secondchannel segment are offset from each other with respect to a horizontalaxis.

These and other aspects, objects, features, and embodiments will beapparent from the following description and the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the accompanying drawings, which are notnecessarily drawn to scale, and wherein:

FIG. 1 illustrates a luminaire mounting structure including a pair ofhanger bar assemblies attached to a plaster frame in accordance with anexample embodiment;

FIG. 2 illustrates a hanger bar assembly in accordance with an exampleembodiment;

FIGS. 3A-3E illustrate cross-sectional views of the hanger bar assemblyof FIG. 2 after the hanger bar members of the hanger bar assembly areinterlocked in accordance with an example embodiment;

FIGS. 4A-4D illustrate views of the hanger bar assembly of FIG. 2 atvarious interlocking stages in accordance with an example embodiment;

FIGS. 5A and 5B illustrate close-up views the stoppage tabs of thehanger bar assembly of FIG. 2 in accordance with another exampleembodiment;

FIG. 5C illustrates a close-up view of stoppage tabs of the hanger barassembly of FIG. 2 in accordance with another example embodiment;

FIGS. 6A-6C illustrate a luminaire structure including the hanger barassemblies of FIG. 1 adjusted in length for use with different supportstructures in accordance with example embodiments; and

FIGS. 7A-7E illustrate various views of attachment tabs of a plasterframe for securing the hanger bar assembly of FIG. 2 to the plasterframe in accordance with an example embodiment.

The drawings illustrate only example embodiments and are therefore notto be considered limiting in scope. The elements and features shown inthe drawings are not necessarily to scale, emphasis instead being placedupon clearly illustrating the principles of the example embodiments.Additionally, certain dimensions or placements may be exaggerated tohelp visually convey such principles. In the drawings, referencenumerals designate like or corresponding, but not necessarily identical,elements.

DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS

In the following paragraphs, example embodiments will be described infurther detail with reference to the figures. In the description, wellknown components, methods, and/or processing techniques are omitted orbriefly described. Furthermore, reference to various feature(s) of theembodiments is not to suggest that all embodiments must include thereferenced feature(s).

Turning now to the figures, particular embodiments are described. FIG. 1illustrates a luminaire mounting structure 100 including a pair ofhanger bar assemblies attached to a plaster frame in accordance with anexample embodiment. The luminaire mounting structure 100 includes afirst hanger bar assembly 102 and a second hanger bar assembly 104. Thefirst hanger bar assembly 102 and the second hanger bar assembly 104 areattached to a plaster frame 106 at opposite sides of the plaster frame106. As illustrated in FIGS. 5A-C, a luminaire housing may be positionedon the plaster frame 106. Generally, the hanger bar assemblies 102 and104 may be used to install a luminaire, such as a recessed luminaire, ina structure such as a ceiling. As described in more detail below, thefirst hanger bar assembly 102 and the second hanger bar assembly 104 areadjustable in length and can be used to install luminaires to structuresthat have different spacings between them.

In some example embodiments, the first hanger bar assembly 102 includesattachment structures 110 and 112. The attachment structures 110, 112are designed to secure the hanger bar assembly 102 to a supportstructure, such as parallel joists, suspended ceiling T-grids, and/orsteel framing. Similarly, in some example embodiments, the second hangerbar assembly 104 includes attachment structures 114 and 116. Theattachment structures 114, 116 are designed to secure to a supportstructure, such as parallel joists, suspended ceiling T-grids, and/orsteel framing. For example, each attachment structure 110, 112, 114, 116may include a respective fastener 116 (e.g., a screw or nail) that maybe used to secure the attachment structures to a support structure.

In an example embodiment, the first hanger bar assembly 102 and thesecond hanger bar assembly 104 are attached to the plaster frame 106 byone or more attachment tabs 108 on the sides of the plaster frame 106.For example, each of the one or more attachment tabs 108 may be elasticand movable to enable the hanger bar assembly 102 or 104 to bepositioned between the respective tab 108 and the rest of the plasterframe 106 as illustrated in FIG. 1. In some example embodiments, each ofthe attachment tabs 108 may also be a loop that is, for example,integrally formed with the plaster frame 106.

FIG. 2 illustrates a hanger bar assembly 200 in accordance with anexample embodiment. The hanger bar assembly 200 of FIG. 2 corresponds tothe first hanger bar 102 and to the second hanger bar 104 of FIG. 1 andthe description of the hanger bar assembly 200 equally applies to thefirst hanger bar 102 and to the second hanger bar 104. As illustrated inFIG. 2, the hanger bar assembly 200 includes a first hanger bar member202 and a second hanger bar member 204. The first hanger bar member 202and the second hanger bar member 204 may be interlocked with each otheras illustrated, for example, in FIGS. 3A and 3B. Once the first hangerbar member 202 and the second hanger bar member 204 are interlocked, thehanger bar assembly 200 is freely adjustable lengthwise (i.e.,longitudinally).

As illustrated in FIG. 2, the first hanger bar member 202 includes arail segment 210, a transitional middle segment 212, and a channelsegment 214. The transitional middle segment 212 extends between therail segment 210 and the channel segment 214. For example, thetransitional middle segment 212 may extend between the rail segment 210and the channel segment 214 for substantially the entire length of therail segment 210. Alternatively, the transitional middle segment 212 mayextend between the rail segment 210 and the channel segment 214 for aportion of the rail segment 210 that is shorter than the entire lengthof the rail segment 210. As more clearly illustrated in FIGS. 3A-3C, thetransitional middle segment 212 may be slanted relative to the railsegment 210 and relative to the channel segment 214. The channel segment214 includes a channel 216, that, in some example embodiments, mayextend for an entire length of the channel segment 214.

In some example embodiments, an attachment structure 206 is attached tothe first hanger bar member 202 at an end of the hanger bar member 202.The attachment structure 206 may be integrally formed with the hangerbar member 202, or may be formed separately and attached to the hangerbar member 202 by a means such as welding or a fastener. The attachmentstructure 206 includes a gap 228 that allows a portion of the secondhanger bar member 204 to extend past the attachment structure 206 whenthe first hanger bar member 202 and the second hanger bar member 204 areinterlocked in a manner illustrated, for example, in FIG. 1. Toillustrate, without the gap 228 in the attachment structure 206, thelongitudinal movement of the second hanger bar member 204 that isinterlocked with the first hanger bar member 202 as shown in FIG. 3Awould be limited by the attachment structure 206 in one direction. Thus,the gap 228 allows the hanger bar assembly 200 to be adjusted to ashorter length than what would otherwise be possible. Other embodimentsof the attachment structures 206, 208 that include a gap, such as thegap 228, are described in U.S. Pat. No. 7,673,841, the content of whichis hereby incorporated herein. The adjustability of the hanger barassembly 200 to a shorter length allows use of the hanger bar assembly200 with support structures such as joists or T-bars that may have anarrow spacing between them.

As illustrated in FIG. 2, the second hanger bar member 204 includes arail segment 220, a transitional middle segment 222, and a channelsegment 224. The transitional middle segment 222 extends between therail segment 220 and the channel segment 224. For example, thetransitional middle segment 222 may extend between the rail segment 220and the channel segment 224 for substantially the entire length of therail segment 220. Alternatively, the transitional middle segment 212 mayextend between the rail segment 210 and the channel segment 214 for aportion of the rail segment 210 that is shorter than the entire lengthof the rail segment 210. As more clearly illustrated in FIGS. 3A and 3B,the transitional middle segment 222 is slanted relative to the railsegment 220 and relative to the channel segment 224. The channel segment224 includes a channel (the channel 302 illustrated in FIGS. 3A and 3B),that, in some example embodiments, may extend for an entire length ofthe channel segment 214.

In some example embodiments, an attachment structure 208 is attached tothe hanger bar member 204 at an end of the hanger bar member 204. Theattachment structure 208 may be integrally formed with the hanger barmember 204, or may be formed separately and attached to the hanger barmember 204 by a means such as welding or a fastener. Similar to theattachment structure 206, the attachment structure 208 includes a gap,similar to the gap 228 of the attachment structure 206, that allows aportion of the first hanger bar member 202 to extend therethrough andpast attachment structure 208 when the first hanger bar member 202 andthe second hanger bar member 204 are interlocked.

The first hanger bar member 202 and the second hanger bar member 204 maybe interlocked by sliding the rail segment 210 of the first hanger barmember 202 into the channel in the channel segment 224 while sliding therail segment 220 of the second hanger bar member 204 into the channel216 of the channel segment 214. When the first hanger bar member 202 andthe second hanger bar member 204 are interlocked, the rail segment 210is positioned in the channel of the channel segment 224 of the secondhanger bar member 204, and the rail segment 220 of the second hanger barmember 204 is positioned in the channel 216 of the channel segment 214of the first hanger bar member 202.

In some example embodiments, the first hanger bar member 202 includes astoppage tab 218 that extends from an edge of the channel segment 214.The second hanger bar member 204 may include a stoppage tab 226 thatextends, for example, from a wall of the channel segment 224. Thestoppage tab 218 and the stoppage tab 226 may be dimensioned such that,once the first hanger bar member 202 and the second hanger bar member204 are interlocked, the stoppage tab 218 and the stoppage tab 226prevent or reduce the risk of unintended detachment of the first hangerbar member 202 and the second hanger bar member 204 from each other.Although the stoppage tab 218 and the stoppage tab 226 prevent or reducethe risk of unintended detachment of the first hanger bar member 202 andthe second hanger bar member 204 from each other, one or both of thestoppage tab 218 and the stoppage tab 226 may be moved to intentionallydetach the first hanger bar member 202 and the second hanger bar member204 from each other. In some example embodiments, one or both of thestoppage tab 218 and the stoppage tab 226 may also be moved to slidablyinterlock the first hanger bar member 202 and the second hanger barmember 204 with each other as illustrated in FIGS. 3A and 3B. Thestoppage tab 218 and the stoppage tab 226 may have spring-like responseto a force that applied in a direction perpendicular the hanger barmembers 202, 204. In some example embodiments, the hanger bar assembly200 is made from sheet metal. For example, the sheet metal may bealuminum sheet metal. In alternative example embodiments, the sheetmetal may be raw steel instead of aluminum. In some example embodiments,the first hanger bar member 202 and the second hanger bar member 204 maybe made by extrusion of metal or other material(s) such as a compositematerial. Alternatively, the first hanger bar member 202 and the secondhanger bar member 204 may be made by molding. The first hanger barmember 202 and the second hanger bar member 204 may be formed such thatthe hanger bar assembly 200 has the strength and rigidity adequate tosupport a luminaire such as a recessed luminaire or another kind ofluminaire that may be supported by the hanger bar assembly 200.

In some example embodiments, the first hanger bar member 202 and thesecond hanger bar member 204 may include score lines 230. For example,after the first hanger bar member 202 and the second hanger bar member204 are assembled as shown in FIG. 1, the hanger bar members 202, 204may be cut, broken, or bent along a respective score line 230 to allowthe hanger bar members 202, 204 to fit between joists.

Although FIG. 2 shows that the attachment structure 206 is attached tothe first hanger bar member 202, and the attachment structure 208 isattached to the second hanger bar member 204, in alternativeembodiments, the hanger bar assembly 200 may not include the attachmentstructures 206 and 208. Alternatively, the hanger bar assembly 200 mayinclude attachment structures that are different from the attachmentstructures 206 and 208.

FIGS. 3A-3E illustrate cross-sectional views of the hanger bar assembly200 of FIG. 2 after the hanger bar members 202, 204 of the hanger barassembly 200 are interlocked with each other in accordance with anexample embodiment. The first hanger bar member 202 and the secondhanger bar member 204 are interlocked such that the rail segment 210 ofthe first hanger bar member 202 is positioned in the channel 302 of thesecond hanger bar member 204, and such that the rail segment 220 of thesecond hanger bar member 204 is positioned in the channel 216 of thefirst hanger bar member 202. As illustrated in FIGS. 3A and 3B, each ofthe channels 216 and 302 may be substantially U-shaped and is defined bywalls of the respective channel segment 214 or 224. For example, thechannel segment 214 has a wall 304 defining the channel 216 on a side ofthe channel segment 214. Similarly, the channel segment 224 has a wall306 defining the channel 302 on a side of the channel segment 224. Insome alternative example embodiments, the channels 216 and 302 may haveshapes other than the substantially U-shape shown in FIGS. 3A and 3B. Asillustrated in FIGS. 3A and 3B, the hanger bar members 202 and 204 areinterlocked to each to form a substantially uniform solid structurehaving a general shape of a rectangular rod with rounded corners.

As illustrated in FIGS. 3A-3C (the attachment structure 206 is omittedfrom FIG. 3C for clarity of illustration), the transitional middlesegment 212 may be slanted relative to the rail segment 210 and relativeto the channel segment 214. Similarly, the transitional middle segment222 may be slanted relative to the rail segment 220 and relative to thechannel segment 224. In an example embodiment, the degree of slant ofthe transitional middle segment 212 relative to the rail segment 210 maybe substantially the same as the degree of slant of the transitionalmiddle segment 222 relative to the rail segment 220. For example, in theorientation of the hanger bar members 202, 204 shown in FIGS. 3A and 3B,the transitional middle segment 212 may be slanted approximately 45degrees relative to a vertical axis extending down from the rail segment210. Similarly, the transitional middle segment 222 may be slantedapproximately 45 degrees relative to a vertical axis extending up fromthe rail segment 220 of the second hanger bar member 204. In an exampleembodiment, when the first hanger bar member 202 and the second hangerbar member 204 are interlocked as illustrated, the transitional middlesegment 212 and the transitional middle segment 222 are substantiallylined up to the extent that the first hanger bar member 202 and thesecond hanger bar member 204 overlap with each other. For example, asurface of the transitional middle segment 212 may be in contact with asurface of the transitional middle segment 222.

As illustrated in FIG. 3D, the transitional middle segment 212 and thetransitional middle segment 222 may be curved instead of slanted.Alternatively, the transitional middle segment 212 and the transitionalmiddle segment 222 may be substantially horizontal as illustrated inFIG. 3E. The rail segment 210 and the channel segment 214 of the firsthanger bar member 202 are offset from each other with respect to ahorizontal axis (X) shown in FIGS. 3C-3E. Similarly, the rail segment220 and the channel segment 224 of the second hanger bar member 204 areoffset from each other with respect to the horizontal axis (X). In somealternative embodiments, the transitional middle segment 212 and thetransitional middle segment 222 may have cross-sectional shapes otherthan shown in FIGS. 3A-3C without departing from the scope of thisdisclosure.

As illustrated in FIGS. 3A and 3B, when the first hanger bar member 202and the second hanger bar member 204 are interlocked with each other,the rail segment 210 of the first hanger bar member 202 is positionedadjacent to the channel segment 224 of the second hanger bar member 204,and the channel segment 214 of the first hanger bar member 202 ispositioned adjacent to the rail segment 220 of the second hanger barmember 204.

The interlocked first hanger bar member 202 and second hanger bar member204 are slidable relative to each other such that the hanger barassembly 200 has an adjustable overall length. In an example embodiment,the second hanger bar member 204 may extend through the gap 228, and thefirst hanger bar member 202 may extend through a similar gap in theattachment structure 208 attached to an end of the second hanger barmember 204 as illustrated in FIG. 2.

FIGS. 4A-4D illustrate views of the hanger bar assembly 200 of FIG. 2 atvarious interlocking stages in accordance with an example embodiment.FIG. 4A illustrates the first hanger bar member 202 and the secondhanger bar member 204 prior to being interlocked with each other. Asshown in FIG. 4A, an end portion 402 is aligned with the channel 216 offirst hanger bar member 202. An end portion 404 of the first hanger barmember 202 is similarly aligned with the channel 302 (shown in FIG. 4C)of the second hanger bar member 204. By extending beyond the stoppagetabs 218, 226, the end portions 402 and 404 aid in the alignment of thefirst hanger bar member 202 and the second hanger bar member 204.

In contrast to FIG. 4A, in FIGS. 4B and 4C, the first hanger bar member202 and the second hanger bar member 204 are in contact with each other.For example, as more clearly illustrated in FIG. 4C, the end portion 404of the first hanger bar member 202 is already positioned in the channel302 of the second hanger bar member 204. In FIG. 4D, the end portion 402of the second hanger bar member 204 has moved closer to the channel 216of the first hanger bar member 202 as compared to the position shown inFIG. 4B.

FIGS. 5A and 5B illustrate close-up views the stoppage tabs 218, 226 ofthe hanger bar assembly 200 of FIG. 2 in accordance with an exampleembodiment. The stoppage tab 218 and the stoppage tab 226 may bedimensioned such that the first hanger bar member 202 and the secondhanger bar member 204 may be interlocked by sliding into each other'schannel as described above while minimizing or preventing unintendeddisengagement/detachment of the first hanger bar member 202 and thesecond hanger bar member 204 from each other.

In a particular embodiment, the stoppage tab 218 extends out from anedge 502 of the channel segment 214 of the first hanger bar member 202.The stoppage tab 218 has a slanted edge 504 and a substantially straightedge 506. The stoppage tab 218 also has a third edge 514 between theslanted edge 504 and the substantially straight edge 506. The channelsegment 214 of the first hanger bar member 202 has a slanted edge 518that continues from the slanted edge 504 of the stoppage tab 218. Thestoppage tab 218 may be integrally formed with the channel segment 214,or may be formed separately and attached to the channel segment 214 bymeans such as welding or a fastener.

In an example embodiment, the stoppage tab 226 extends out from a wallof the channel segment 224 of the second hanger bar member 204. Forexample, the stoppage tab 226 may be formed from a portion of thechannel segment 224 and a portion of the transitional middle segment222. Alternatively, the stoppage tab 226 may be attached to the channelsegment by a means such as welding or a fastener. The stoppage tab 226may have a substantially straight edge 510 and a slanted edge 508forming a corner with the substantially straight edge 510. The stoppagetab 226 also has another edge 512 that is shorter than the substantiallystraight edge 510. The edge 512 forms a corner with the slanted edge 408that is different from the common corner the slanted edge 408 forms withthe substantially straight edge 510. Thus, the slanted edge 508 isslanted upwards as the slanted edge 508 extends from the substantiallystraight edge 510 toward the other edge 512.

When interlocking the first hanger bar member 202 and the second hangerbar member 204, the slanted edge 508 of the stoppage tab 226 may slideover the slanted edge 504 and over the third edge 514 of the stoppagetab 218. For example, the stoppage tab 226 may be pushed over theslanted edge 504 and over the third edge 514 of the stoppage tab 218.Alternatively, one or both of the stoppage tabs 218 and 226 may bepushed or pulled perpendicular to the longitudinal axis of the hangerbar assembly 200 while pushing one or both of the first hanger barmember 202 and the second hanger bar member 204 longitudinally towardseach other to interlock the first hanger bar member 202 with the secondhanger bar member 204.

Once the first hanger bar member 202 and the second hanger bar member204 are interlocked such that the substantially straight edge 510 of thestoppage tab 226 is positioned adjacent to the substantially straightedge 506 of the stoppage tab 218, the stoppage tabs 218 and 226 mayminimize and/or prevent unintended disengagement of the hanger barmembers 202 and 204 from each other. As illustrated in FIG. 5A, thestoppage tabs 218 and 226 can abut against each other to preventunintentional detachment of the hanger bar members 202 and 204 from eachother. Once interlocked as shown in FIG. 5A, the hanger bar members 202and 204 can be moved longitudinally relative to each other to adjust thelength of the hanger bar member 200 as shown in FIG. 5B. Tointentionally disengage/detach the first hanger bar member 202 and thesecond hanger bar member 204 from each other, one or both of the tabs218 and 226 may be pushed or pulled slightly perpendicular to thelongitudinal axis of the hanger bar assembly 200 while pulling one orboth of the first hanger bar member 202 and the second hanger bar member204 away from one another. Although stoppage tabs 218 and 226 aredescribed as a means for minimizing or preventing unintendeddisengagement of the hanger bar members 202 and 204 from each other, inalternative embodiments, other structures and/or methods may be used tominimize and/or prevent unintended disengagement of the hanger barmembers 202 and 204.

FIG. 5C illustrates a close-up view of the stoppage tabs 218, 226 of thehanger bar assembly 200 of FIG. 2 in accordance with another exampleembodiment. In some example embodiments, the first hanger bar member 202may include an extended end portion 530 that extends beyond the stoppagetab 218. In contrast to the slanted edge 518 that extends from theslanted edge 504 of the stoppage tab 218 shown in FIGS. 5A and 5B, theextended end portion 530 is a portion of the channel 216 shown in FIG.2.

FIGS. 6A-C illustrate a luminaire structure 600 including the hanger barassemblies 102 and 104 of FIG. 1 adjusted in length for use withdifferent support structures in accordance with example embodiments. Asindicated above, each of the hanger bar assemblies 102 and 104corresponds to the hanger bar assembly 200 described above. In aparticular embodiment, the hanger bar assemblies 102 and 104 correspondto the hanger bar assembly 200 of FIGS. 2-4. FIG. 6A illustrates thehanger bar assemblies 102 and 104 in a fully extended position. Forexample, when the hanger bar assemblies 102 and 104 are in a fullyextended position, the stoppage tabs 218 and 226 of each hanger barassembly 102 and 104 may be in contact with each other in a manner shownin FIG. 4.

FIG. 6B illustrates the hanger bar assemblies 102 and 104 in a fullyretracted position. As illustrated in FIG. 6B, each hanger bar member ofthe first hanger bar assembly 102 may extend beyond the attachmentstructure 110, 112 (more clearly shown in FIG. 1) attached to the othermating hanger bar member of the hanger bar assembly 102. Similarly, eachhanger bar member of the second hanger bar assembly 104 may extendbeyond the attachment structure 114, 116 (more clearly shown in FIG. 1)attached to the other mating hanger bar member of the second hanger barassembly 104. In some example embodiments, the portions of the hangerbar members of the hanger bars assemblies 102, 104 shown as extendingbeyond the respective attachment structures 110, 112, 114, 116 may bebent, broken off, or cut off (for example, along the score line 230shown in FIG. 2) for attachment to a support/installation structure suchas joists.

FIG. 6C illustrates the hanger bar assemblies 102 and 104 in a positionbetween the fully extended position shown in FIG. 6A and the fullyretracted position shown in FIG. 6B. As illustrated in FIGS. 6A-C, eachof the hanger bar assemblies 102 and 104 may be adjusted for use withsupport structures that have various spacing between them correspondingto a range between the fully extended positions of the hanger barassemblies 102, 104 shown in FIG. 6A and the fully retracted positionsshown in FIG. 6B. For example, the hanger bar assemblies 102 and 104 maybe adjusted in length for use with support structures that are between12 inches and 24 inches apart. In some example embodiments, the hangerbar assemblies 102 and 104 may be adjusted to less than 12 inches and/orto greater than 24 inches. As illustrated in FIGS. 6A-6C, the hanger barassemblies 102 and 104 can support a luminaire housing 602 that ispositioned on the plaster frame 106 along with other fixture components,such as the junction box 604 and one or more light sources that may bepositioned in the luminaire housing 602.

FIGS. 7A-7E illustrate various views of attachment tabs of the plasterframe 106 for securing the hanger bar assembly of FIG. 2 to the plasterframe 106 in accordance with an example embodiment. As illustrated inFIGS. 7A-7C, the hanger bar assembly 200 is attached to the plasterframe 106 by the attachment tabs 108. In some example embodiments, theattachment tabs 108 may formed from portions of the plaster frame 106including an edge portion 702 of the plaster frame 106. Alternatively,the attachment tabs 108 may be attached to the plaster frame 106 bymeans such as soldering.

In some example embodiments, the attachment tabs 108 include a rib 704,as more clearly shown in FIGS. 7B and 7C. For example, the rib 704 maybe formed in the attachment tab 108 by methods such as pressing. As thelength of the hanger bar member 200 is adjusted, the rib 704 can reducethe contact surface area between the attachment tab 108 and the hangerbar assembly 200. To illustrate, because the rib 704 extends toward thewall 304 of the first hanger bar member 202, the rib 704 may be incontact with only the surface of the wall 304 of the first hanger barmember 202. During installation of a luminaire structure (e.g., theluminaire structure 600 of FIG. 6A) to structures such as joists, therib 704 of each attachment tab 108 guides the hanger bar members 202,204 away from an outer wall 712 of the attachment tabs 108 and throughthe attachment tabs 108 as the length of the hanger bar members assembly200 is adjusted by slidably moving one or both of the hanger bar members202, 204.

When the hanger bar assemblies 102, 104 are fully or substantiallyextended (e.g., luminaire structure 600 of FIG. 6A), only one of the twohanger bar members 202, 204 may be positioned in a particular attachmenttab 108 as illustrated in FIGS. 7D and 7E. For example, as illustratedin FIG. 7D, when the first hanger bar member 202 is positioned in theparticular attachment tab 108, the channel segment 214 of the hanger barmember 202 may be in physical contact with or very close to the rib 704of the respective attachment tab 108 and a back wall 710 of plasterframe 106. Similarly, as illustrated in FIG. 7E, when the second hangerbar member 204 is positioned in the particular attachment tab 108, thechannel segment 224 of the hanger bar member 204 may be in physicalcontact with or very close to the rib 704 of the respective attachmenttab 108 and the back wall 710. Because the channel segments 214, 224 ofthe hanger bar members 202, 204 may be in physical contact with or veryclose to the rib 704 of the respective attachment tabs 108 and the backwall 710, lateral movements of hanger bar members 202, 204 within therespective attachment tab 108 (i.e., toward and way from the rib 704 andthe back wall 710) are significantly limited. Such limitation on thelateral movement of the hanger bar members 202, 204 results in thestability of the installed luminaire structure, such as the luminairestructure 600 of FIG. 6A.

Although the attachment tabs 108 are shown as having a particular shape,in some alternative embodiments, the attachment tabs 108 may have othershapes without departing from the scope of this disclosure. For example,the attachment tabs 108 may have more than one rib 704.

Although particular embodiments have been described herein in detail,the descriptions are by way of example. The features of the exampleembodiments described herein are representative and, in alternativeembodiments, certain features, elements, and/or steps may be added oromitted. Additionally, modifications to aspects of the exampleembodiments described herein may be made by those skilled in the artwithout departing from the spirit and scope of the following claims, thescope of which are to be accorded the broadest interpretation so as toencompass modifications and equivalent structures.

What is claimed is:
 1. A plaster frame for a luminaire, comprising: afirst attachment tab on a side of the plaster frame; a second attachmenttab on the side of the plaster frame; and a back wall, wherein the firstattachment tab and the second attachment tab each comprise a ribprotruding toward the back wall, wherein the back wall and the firstattachment tab define a first space for a hanger bar assembly to extendtherethrough, wherein the back wall and the second attachment tab definea second space for the hanger bar assembly to extend therethrough, andwherein the rib of the first attachment tab extends along portions ofupper and lower half sections of the first attachment tab.
 2. Theplaster frame of claim 1, wherein the rib of the first attachment tab isformed in a wall of the first attachment tab and protrudes toward theback wall away from the wall of the first attachment tab.
 3. The plasterframe of claim 2, wherein the rib of the second attachment tab is formedin a wall of the second attachment tab and protrudes toward the backwall away from the wall of the second attachment tab.
 4. The plasterframe of claim 2, wherein the rib of the first attachment tab is shapedto guide the hanger bar assembly away from the wall of the firstattachment tab during adjustment of the hanger bar assembly.
 5. Theplaster frame of claim 1, wherein the first attachment tab and thesecond attachment tab extend down from an edge portion of the plasterframe on a first side of the edge portion.
 6. The plaster frame of claim5, wherein the back wall extends down from the edge portion of theplaster frame on a second side of the edge portion.
 7. The plaster frameof claim 5, wherein the edge portion, the first attachment tab, and thesecond attachment tab are integrally formed with each other.
 8. Theplaster frame of claim 1, further comprising a third attachment tab anda fourth attachment tab on a second side of the plaster frame, whereinthe third attachment tab and the fourth attachment tab each comprise arib protruding toward a second back wall of the plaster frame.
 9. Theplaster frame of claim 8, wherein the second back wall and the thirdattachment tab define a third space for a second hanger bar assembly toextend therethrough, and wherein the second back wall and the fourthattachment tab define a fourth space for the second hanger bar assemblyto extend therethrough.
 10. A luminaire mounting structure for mountinga recessed luminaire, the luminaire mounting structure comprising: ahanger bar assembly comprising a first hanger bar member and a secondhanger bar member, wherein a rail segment of the second hanger barmember is positioned in a channel of a channel segment of the firsthanger bar member; and a plaster frame comprising: a first attachmenttab disposed on a side of the plaster frame; a second attachment tabdisposed on the side of the plaster frame; and a back wall, wherein thefirst attachment tab and the second attachment tab each comprise a ribprotruding toward the back wall, wherein the hanger bar assembly ispositioned between the back wall and the first attachment tab andbetween the back wall and the second attachment tab, and wherein the ribof the first attachment tab is in contact with the channel segment ofthe first hanger member.
 11. The luminaire mounting structure of claim10, wherein the rib of the first attachment tab is formed in a wall ofthe first attachment tab and protrudes toward the back wall away fromthe wall of the first attachment tab.
 12. The luminaire mountingstructure of claim 11, wherein the rib of the second attachment tab isformed in a wall of the second attachment tab and protrudes toward theback wall away from the wall of the second attachment tab.
 13. Theluminaire mounting structure of claim 11, wherein the rib of the firstattachment tab is shaped to guide the hanger bar assembly away from thewall of the first attachment tab during adjustment of the hanger barassembly.
 14. The luminaire mounting structure of claim 10, wherein thesecond hanger bar member comprises a second channel segment having asecond channel and wherein a rail segment of the first hanger bar memberis positioned in a channel of the second channel segment.
 15. Theluminaire mounting structure of claim 14, wherein the rib of the secondattachment tab is in contact with the second channel segment of thesecond hanger bar.
 16. The luminaire mounting structure of claim 10,wherein the first attachment tab and the second attachment tab extenddown from an edge portion of the plaster frame on a first side of theedge portion and wherein the back wall extends down from the edgeportion of the plaster frame on a second side of the edge portion. 17.The luminaire mounting structure of claim 10, wherein the plaster framefurther comprises a third attachment tab and a fourth attachment tab ona second side of the plaster frame and wherein the third attachment taband the fourth attachment tab each comprise a rib protruding toward asecond back wall of the plaster frame.
 18. The luminaire mountingstructure of claim 17, wherein a second hanger bar assembly ispositioned between the second back wall and the third attachment tab andbetween the second back wall and the second attachment tab.
 19. Aplaster frame for a luminaire, comprising: a first attachment tab on aside of the plaster frame; a second attachment tab on the side of theplaster frame; and a back wall, wherein the first attachment tab and thesecond attachment tab each comprise a rib protruding toward the backwall, wherein the back wall and the first attachment tab define a firstspace for a hanger bar assembly to extend therethrough, wherein the backwall and the second attachment tab define a second space for the hangerbar assembly to extend therethrough, wherein the rib of the firstattachment tab comprises a first protrusion and a second protrusion thatprotrude toward the back wall, and wherein the rib of the firstattachment tab is positioned to come in contact with a channel segmentof a hanger member of the hanger bar assembly when the hanger member ofthe hanger bar assembly extends through the first space.
 20. The plasterframe of claim 19, wherein the rib of the first attachment tab is formedin a wall of the first attachment tab and protrudes toward the back wallaway from the wall of the first attachment tab.